<div class="gmail_quote">On Fri, Dec 4, 2009 at 4:28 PM, John Smith <span dir="ltr"><<a href="mailto:deltafoxtrot256@gmail.com">deltafoxtrot256@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
2009/12/4 Steve Bennett <<a href="mailto:stevagewp@gmail.com">stevagewp@gmail.com</a>>:<br>
<div class="im">> Again, this proposal is not primarily about rendering. That's a nice benefit<br>
> in some cases. The goals are:<br>
> 1) More appropriate data structure<br>
<br>
</div>How is this more appropriate, you are loosing real world information<br>
to improve rendering.<br></blockquote><div><br>The main focus is *adding* information to roads currently mapped as single (non-divided) roads. Gaining information. Not losing. There are a huge number of places that this will add information that was not previously mapped. <br>
<br>I don't know how to convince you that I'm not proposing changing the way major roads and dual carriageways are mapped. This is about minor divisions in minor roads.<br><br>Let me ask you: how do you think that a road with a painted traffic island down the middle should be mapped:<br>
1) As a single road with no special tagging<br>2) As a single road with a tag indicating the division<br>3) As two separate ways, with ways connecting them every time there's a gap in the painted division.<br><br>Here's an example that we can use to discuss (use satellite view):<br>
<b><a href="http://tinyurl.com/y8cxujs">http://tinyurl.com/y8cxujs</a><br></b><b><br></b>If you would like to propose some rules for the use of this tagging (like don't use it for dual carriageways), that would be helpful.<br>
<br>> 2) Better usability<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
How does this improve useability at all?<br></blockquote><div><br>Because adding a single tag is a lot simpler than making two parallel ways.<br>Because modelling one road as is easier than modelling one road as two roads.<br>
<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div class="im">> 3) Better rendering at no effort.<br>
<br>
</div>Number 3 shouldn't be a goal, just like using the layer tag shouldn't<br>
be used to alter the rendering order.<br>
</blockquote></div><br>Better rendering should always be a goal. What I think you mean is "we shouldn't modify the way we map in order to compensate for some short-term deficiency in current renderers". I agree. I think modelling minor streets that have median strips as single roads is the right thing to do. Better rendering is just an additional benefit. If there was a trade-off between them, we would go with correct modelling.<br>
<br>Steve<br>